The present invention relates to improved coated medicaments and apparatus and methods for making such improved products.
The desirability of manufacturing medicaments having a gelatinous or other coating is pointed out in U.S. Pat. No. 4,820,524 which is incorporated in its entirety herein by reference. Although the invention disclosed therein fulfilled, to a certain extent, the need for a coated medicament which is at least as a tamper resistant as a caplet, yet still provides the ease of swallowability of a capsule, the need for further refinements in this regard remains unmet.
The concept of coated pills and tablets is well known in the art. There are numerous reasons for employing such coatings. Most frequently, the coating will either protect the linings of the digestive tract from direct contact with the compressed tablet or provide a time release function by slowing the dissolution rate. In many instances, coatings also protect the tablets from physical damage or deterioration during shipment and handling.
Numerous medicaments have traditionally been provided by filling hard gelatin capsules with active ingredients. The unexpected increase in the occurrence of product tampering incidents involving hard gelatin capsules created an urgent need for new tamper resistant packaging. In creating such packaging, an important factor was the retention of the physical characteristics of a gelatin capsule. There exists evidence that gelatin coated medicaments are easier for many patients to swallow. Additionally, there is a perception that medicaments provided in hard gelatin capsules are more effective. This latter effect is similar to the placebo effect, patients maintaining that a capsule form medicament is more effective, even if the non-capsule form prescribed is of equal pharmacological effectiveness.
In response to this need, it has been found that an oblong-shaped caplet, or other solid form of medicament may be coated with gelatin to provide both the easier swallowability and the outward appearance of a hard gelatin capsule. Accordingly, U.S. Pat. No. 4,820,524 provides a coated medicament which is at least as tamper-resistant as a caplet, while providing the easy of swallowability of a gelatin capsule. The capsule-like medicaments provided have smooth, relatively thick, shiny, multi-colored gelatinous coatings thereon. The medicaments disclosed are pleasing to the eye and are intended to be perceived by patients to be easier to swallow and more effective than caplets having other coatings, while providing greater tamper resistance than conventional capsules.
Other types of coatings in addition to gelatin are known to those of ordinary skill. For example, U.S. Pat. No. 4,585,764--Bailey discloses combining aspirin with 3.3'-hiobis, while U.S. Pat. No. 4,590,183--Bailey provides combining aspirin with sodium thiosulfate. Both Bailey patents are directed to the cytoprotection of gastric mucosa using the coatings described. U.S. Pat. No. 4,713,248--Kjern, et al, discloses a coating for a medicament comprising a polymer film which provides a controlled release coating. The preferred coating is a substantially water insoluble but water diffusible polymer. An improved tablet or caplet comprised citric, alginic or glutamic acid is disclosed in U.S. Pat. No. 4,716,042--Blank, et al. Undoubtedly, those of ordinary skill are aware that these and other coatings may be modified, combined or used in conjunction with one another. Moreover, certain of these may be useful in combination with gelatin to form a coated product in accordance with the present invention.
Although the coated caplets disclosed in U.S. Pat. No. 4,820,524 described immediately above provide a novel and superior product which has met with outstanding commercial success, that success has created new challenges and a need for further refinements and improvements. For example, at present, coated caplet products having different portions of the coating overlapped to form a seam, thereby creating a simulated capsule-like medicament are most preferably provided. However, the overwhelming acceptance of gelatin coated caplets has created a need for variations to the original product. In other instances, it may be preferable that the coatings do not overlap, but instead leave a "line" of underlying uncoated material. These embodiments may be preferable for brand identification or for other purposes. Also, it has now been found that the simulation of a capsule-like appearance may no longer be necessary to overcome any consumer acceptance problems which may have initially existed.
Although methods of producing pills having smooth continuous gelatin coatings are generally known, products produced by such methods are necessarily of limited utility. For example, U.S. Pat. No. 599,865--Richards discloses fully coated pills produced by a method which eliminates holes or discontinuities caused by the point of contact with pill handling apparatus used at that time. Richards, however, provides no teaching regarding the creation of a product having two or more colors or the control of the extent to which the pill is coated, e.g. one-half, one third, etc. Thus, there exists a need for gelatin coated products which are dipped in gelatin and do not have a seam created by the overlap of the two coatings even if only one color is used.
Despite the teachings of the patents referenced above and U.S. Pat. 4,820,524 which discloses an overlapped capsule-like gelatin coated product, a need remains for enhanced gelatin coated products in a wider variety of available configurations. Further, it is desirable that such coated medicaments lend themselves to efficient manufacturing processes. Although U.S. Pat. No. 4,820,524 provides an inexpensive medicament coating method capable of producing a multi-colored capsule-like coating which is perceived by the consuming public to be more effective, this and previous inventions are at best interim solutions. Previous methods and apparatus were directed to modifying existing hard gelatin capsule machinery for coating solid medicaments. This was a practical and valuable solution, allowing these novel products to be produced with a minimum lead time. The outstanding success of the product produced, however, has created an urgent need for methods and apparatus which can produce a multi-colored capsule-like coating faster, more efficiently, at higher volumes and at higher levels of coating quality and consistency than previously possible. It is further desirable to be able to introduce a variety of coating combinations beyond the "half a first color, half a second color" format generally in use, and to be able to produce these and other gelatin coated products efficiently. Finally, it is desirable to use more than one coating-of a substance or substances. Such a product may have multiple coatings which provide a smoother finish. Moreover, the products to which coatings are applied may or may not have a subcoat.